Needle bar for knitting machines

ABSTRACT

The knitting head is divided, parallel to the looping area, into two parts firmly fixed together. The first part carries a plurality of knocking off bits and delimits frontally the tricks in which the needles move. The second part carries a plurality of spacers which are aligned with and form extensions of the knocking off bits and delimits laterally the tricks.

United States Patent Dalmau Giiell May 23, 1972 [s41 NEEDLE BAR FOR KNITTING 3,290,900 12/1966 Whitehead ..66/1 15 MACHINES 3,237,430 3/1966 Schmidt ..66/1 15 x u 1,115,129 11/1914 Swinglehurst ..66/115 [721 Invent: Mafia cue", Badalma Spam 1,850,817 3/1932 Swinglehurst ..66/1 15 [73] Assignee; Jumbem, SOA Jacinto Benavente 5/ 2,508,834 5/1950 M11161 ..66/1 15 Badalona (Prov, Barcelona), Spain 3,176,479 4/1965 N011 ..66/1 15 ,301,014 1967 1 221 Filed: Nov. 24, 1969 3 H wesmger 66/ 1 App, 879,447 FOREIGN PATENTS OR APPLICATIONS 849,529 1/1939 France .66/l 15 52 us. c1. ..66/1 15 707,390 6/194 German! 5 1 Int Cl D u 15/00 1,145,080 3/1969 Great Bmam (16/1 1 5 [58] Fieldofsearch ..66/115, 104

Primary Examiner-Ronald Feldbaum 5 Referenm Cited Attorney-Patron, Bell, Seltzer, Park & Gibson UNITED STATES PATENTS [57] ABSTRACT 435,174 8/1890 1 Gilbert ..66/104 The knitting head is divided parallel to the looping area, into 552,805 1/1896 Williams ..66/104 two parts firmly fixed together. The first part carries a plurali- 554,475 2/1896 Carledge (it 3.1 "66/104 ty of knocking off bits and delimits frontally the tricks in 606,094 6/1898 Skevington et which the needles move. The second part carries a plurality of 1 ,1 Scott ..66/1 pacers are and form extensions of the 1,406,254 2/1922 Ballard ..66/104 knocking ff bits and delimits laterally the tricks, 2,661,613 12/1953 Mishcon et a1. ..66/1l5 3,084,528 4/1963 Philip ..66/1 15 X 3 Claims, 9 Drawing Figures PATEMTEUMAY NIQR f I 3.664.155

' sum1uF3 INVENTOR JosE-MAmAbALMAU GU ELL ATTORNEYS PATENTEDMM 23 m2 SHEU 2 BF 3 INVENTOR IosE- MAEAA DALMAU 6U E L\ ATTORNEY5 PATENTEDMAYNIBYZ 3,664,155

' SHEET 3 0F 3 I v NTO-RI' .Tose-M mA ieALM GUELL ATTORNEYS NEEDLE BAR FOR KNITTING MACHINES This invention relates to a knitting head for knitting machines, of the type comprising a knitting head body, a plurality of spacers delimiting laterally transverse tricks in which the needles move, and knocking ofi bits aligned with and forming an extension of said spacers towards the looping area. Among the above type of knitting heads are to be found, particularly, those of which the spacers are demountable and are inserted in slots cut into said knitting head body.

As is known, as a result of the movement of the knitting head with respect to suitable cam holder means, the needles perform along said tricks the longitudinal movements necessary for the loop or stitch forming operation, in which knocking off bits cooperate. In some cases a further knitting head operates with the first knitting head, and in a staggered position with respect to the needles of the first knitting head. During the working phase, the front of the needles, that is, the part bearing the hook and latch, emerges periodically from the knitting head beyond the knocking off bits and enters in the looping area, whereby the needle behaves, mechanically, with respect to said tricks, like a cantilever beam. The yam being knitted in the machine, on the one hand, and the knitted material being produced, on the other hand, produce stresses on the emerging part and force the needle against the side walls and bottom of said tricks. These stresses, together with the repetition of the longitudinal movements of the needles, produce a filing action which tends to wear the bottom and side walls of the tricks. The filing action is greater on the bottom than against the side walls, but it is in the latter case where the risk of breakage is greater, since the spacers are subjected to flexure and are relatively thin; consequently it is convenient that these spacers should have various mechanical properties (hardness, brittleness, flexibility, etc.). Nevertheless, in known knitting heads, the side walls and the bottom of the tricks formed in one piece so that it becomes difficult to make the respective mechanical properties sufficiently different to adapt themselves as they should to the different working conditions.

In a similar way, because of the yarn friction and the loop knocking off action, the knocking off bits are subjected to a filing action which is less than that applied to the bottom of the tricks but which is also accompanied by flexures liable to cause breakages. Therefore, it is likewise convenient that the knocking off bits should have mechanical properties which differ from those of the trick bottom, which in practice is difficult to achieve at the present time since, in known knitting heads, these two parts are formed in one piece. On the other hand, should any of the bits be accidentally broken, the whole part, that is, the whole knitting head body, is put out of service.

One object of the invention is to provide a knitting head, the tricks of which are suitable for providing long lasting and correct guidance for the needles.

A further object is to provide a knitting head in which the side walls and bottoms are formed of materials especially suited to withstand wear.

A further object is to provide a knitting head, the knocking off bits of which are suitable to withstand mechanical actions without premature wear and without risk of breakage.

Yet a further object is to provide a knitting head, the knocking off bits of which are individually replaceable once they have been subjected to excessive wear or accidental breakage.

The knitting head according to the invention is characterized by the fact that: (a) the knitting head body is divided, on a plane parallel to the looping area, into a first part and a second part which are firmly joined together; (b) the knocking off bits consist of small replaceable plates inserted into and held in said first part; (c) the first part extends together with and along the looping area, being provided with cuts made perpendicularly to said area, in which the small replaceable plates are inserted and presenting beside said cuts a flat which forms the front part of the bottom of said tricks; and (d) the second part carries the spacers forming the side walls of the tricks in which the machine needles move.

Preferably, also according to the invention, the second part extends towards the looping area and presents a surface facing the first part and reaching up to the knocking off bits; the spacers carried by the second part reach up to the knocking off bits, whilst the part of the second part forming the bottom of the tricks reaches up to the first part.

With reference to the replaceable plates forming the knocking off bits, they may be bonded to the first part by way of adhesive and extensions which are housed in the cuts of the first part, and it is preferred that the extensions should have windows or openings to be filled with the adhesive and thereby cooperate in the fixing of the small replacement plates.

Moreover, in the case of knitting heads with demountable spacers which are inserted in slots cut into the knitting head body, the invention allows for the slots to be cut into the second part and extend towards the surface facing the first part.

It must be pointed out that the knitting heads according to the invention are applicable to both flat and circular knitting machines and that the latter may have both two needle cylinders and needle dial and needle cylinder.

. The attached drawings show two embodiments of the invention as illustrative but not limitative examples.

FIG. 1 is a vertical cross section of two knitting heads according to the invention, applied to a machine with a needle dial and a needle cylinder, showing the respective needles in the point of maximum emergence;

FIGS. 2 and 3 are elevation and plan views of a part of the lower knitting head or needle cylinder of FIG. 1, observed respectively from the trick side and from above. This knitting head is without needles and for greater clarity in the representation, it is supposed that the cylinder has been projected on a plane and that the spacers and the knocking off bits have been eliminated at the left;

FIG. 4 is a cross section taken along line IV-IV of FIG. 2;

FIGS. 5 and 6 are cross sections taken along lines VV and VI-VI of FIGS. 2 and 4;

FIG. 7 is a section similar to FIG. 4 but shows the diverse component members of the knitting head in exploded form whilst retaining their respective positions;

FIG. 8 is a section similar to FIG. 4 but corresponding to a different embodiment of the invention with integral spacers; and

FIG. 9 is a cross section taken along the line IX-IX of FIG. 8.

In FIG. 1, the needle dial or upper knitting head 20 and the needle cylinder or lower knitting head 21 are to be seen provided with needles 22, the front part of which is equipped with a hook 23 and latch 24. The needles move in transverse tricks 25 in a longitudinal direction according to the arrows F. The knitted material 26 produced tends to force the needles 22 inwardly against the bottom of the tricks 25; on the other hand, the yarn (not shown) being knitted in the machine exerts forces perpendicular to the plane of the drawing and tends to force theneedles against the side walls of the tricks. The looping or stitch forming area is marked Z and Z (FIGS. 2, 3 and 5) and the knocking off bits are marked 27.

In FIGS. 2 to 7, it is seen that the knitting head body is broken down into a first part A and a second part B firmly joined together by the thread 28. The separation between A and B takes place parallel with the looping area Z-Z. Part A is closer to the area Z-Z than is part B and extends beside and along the area Z-Z'.

Said first part A, in the region closest to area Z-Z, is provided with cuts 29 made perpendicularly to said area and presents beside said cuts 29 a flat portion 30 which forms the front area of the bottom of the tricks 26. The cross section of said part A gradually narrows on approaching said cuts 29 as may be seen in FIG. 7.

The loop knocking off bits comprise small replaceable plates 27 provided with triangular extensions 27' designed for being housed in the cuts 29 of part A; the thickness of the small plates 27 is substantially equal to the width of the cuts 29. By using adhesive products known in the market for sticking metal parts together, the small plates 27, after being introduced into the cuts 29, are fixed to part A.

It has been observed that, in certain cases, when the triangular extensions 27 are introduced into the cuts 29, a large proportion of the adhesive product is driven out, whereby the small plates 27 are held only weakly with the risk of breaking away whilst the machine is running. In order to fix them suitably, the invention provides for these extensions 27 to have windows or openings 31 which fill with adhesive and ensure good bonding of the small plates 27 even when a greater or lesser amount of the remaining adhesive is driven out when the extensions 27 are introduced into the cuts 29. Once the adhesive filling the windows 31 has set, it acts as a pin to hold the replaceable plates 27 fixedly in part A, with necessary reliability for the machine running. But a further surprising effeet is obtained in that by striking the bits 27 sharply with a punch, these break away cleanly and may be replaced by further new bits, which is of great advantage when the old bits have suffered excessive wear or accidental breakage.

The second part B extends at its front end towards the looping area Z-Z' and presents a surface 32 which faces said first part A and reaches up to the knocking off bits 27. Said part B carries spacers 33 which also reach, at their front end 33', that is, the part directed towards area Z-Z' up to the knocking off bits 27 and which, by their side walls 34 limit the tricks in which the machine needles move. The spacers 33 and knocking off bits 27 are aligned in such a way that the knocking off bits 27 act as extensions of the spacers 33 towards the looping area Z-Z. The part of part B which forms the bottom 35 of the tricks 25 reaches up to surface 32, consequently up to the first part A and is aligned with flat of the part A which forms the front part of the trick bottom.

In the embodiment shown in FIGS. 2 to 7, the spacers 33 are demountable and are held inserted in slots 36 which are cut into the second part B and extend towards surface 32 which faces the first part A. On the other hand, in the embodiment shown in FIGS. 8 and 9, the spacers 33 form part of part B which does not prevent the front part 33 of the spacer and the flat 30 forming the front region of the trick bottom from having sufficiently different mechanical properties, since the flat 30 does not belong to part B but to part A.

What I claim is:

1. An improved knitting head for knitting machines having a set of longitudinally movable needles, said knitting head comprising a body having an elongate looping area at one extremity thereof and being divided to provide a first part (A) and a second part (B) firmly fixed together, said first and second parts extending beside and along said looping area, said first part having cuts (29) perpendicular to said area with flats (30) between each of said cuts and defining a number of transverse tricks in which said needles move, a plurality of knocking off bits (27) over which yarn is drawn by said needles in fonning stitch loops of the knit material and comprising small replaceable plates inserted in said cuts of said first part, said replaceable plates being firmly held in said cuts by an adhesive, said replaceable plates each including openings extending transversely thereof and the adhesive filling the openings to thereby hold said replaceable plates in position, the crosssectional area of said first part gradually narrowing on approaching the knocking off bits, a plurality of spacers (33) carried by said second part and laterally defining needle tricks therein, the cross-sectional area of said second part gradually narrowing on approaching the knocking off bits, said second part extending to said knocking off bits, and said knocking off bits (27) being aligned with and forming extensions to said spacers (33) in the looping area, the gradual narrowing of said first and second parts toward the looping area permitting the knit material to be drawn away from the looping area and the needles at an acute angle.

2. A knitting head according to claim 1 wherein said spacers (33) carried by said second part (B) extend to the knocking off bits.

3. A knitting head according to claim 1 wherein said first and second parts define a needle cylinder (21) with cylinder latch needles supported for vertical movement therein, and including further first and second parts defining a dial (20) with dial latch needles supported for horizontal movement therein, said first and second parts of said dial being substantially identical to said first and second parts of said needle cylinder to permit the looping areas of said dial and said needle cylinder to be positioned closely adjacent each other and to permit the knit material ,to be drawn therebetween. 

1. An improved knitting head for knitting machines having a set of longitudinally movable needles, said knitting head comprising a body having an elongate looping area at one extremity thereof and being divided to provide a first part (A) and a second part (B) firmly fixed together, said first and second parts extending beside and along said looping area, said first part having cuts (29) perpendicular to said area with flats (30) between each of said cuts and defining a number of transverse tricks in which said needles move, a plurality of knocking off bits (27) over which yarn is drawn by said needles in forming stitch loops of the knit material and comprising small replaceable plates inserted in said cuts of said first part, said replaceable plates being firmly held in said cuts by an adhesive, said replaceable plates each including openings extending transversely thereof and the adhesive filling the openings to thereby hold said replaceable plates in position, the cross-sectional area of said first part gradually narrowing on approaching the knocking off bits, a plurality of spacers (33) carried by said second part and laterally defining needle tricks therein, the cross-sectional area of said second part gradually narrowing on approaching the knocking off bits, said second part extending to said knocking off bits, and said knocking off bits (27) being aligned with and forming extensions to said spacers (33) in the looping area, the gradual narrowing of said first and second parts toward the looping area permitting the knit material to be drawn away from the looping area and the needles at an acute angle.
 2. A knitting head according to claim 1 wherein said spacers (33) carried by said second part (B) extend to the knocking off bits.
 3. A knitting head according to claim 1 wherein said first and second parts define a needle cylinder (21) with cylinder latch needles supported for vertical movement therein, and including further first and second parts defining a dial (20) with dial latch needles supported for horizontal movement therein, said first and second parts of said dial being substantially identical to said first and second parts of said needle cylinder to permit the looping areas of said dial and said needle cylinder to be positioned closely adjacent each other and to permit the knit material to be drawn therebetween. 